Conventional video special effect techniques include a time slicing technique, a 360 degree panoramic image technique, and the like.
First, the time slicing technique refers to an imaging technique such that a plurality of cameras is installed around a subject at various angles and a constant interval, the subject is instantaneously photographed simultaneously by the cameras, and then the photographs are connected using a computer, whereby still movement of the subject is viewed as if it is photographed by a movie camera. Although this technique is a method of taking a motion picture using a still camera, the subject stands still. The technique is a certain type of photograph-using animation technique where the still subject is three-dimensionally depicted. When a smoking person is photographed using this technique, a camera motion that circles one revolution around the person may be made without image disconnection while the person and smoke from the person, frozen in the air, stand still.
In other words, one frame of an image can be three-dimensionally depicted in one shot. Thus, the image seems like beyond time and space. Generally, 20 to 50 still cameras are installed circularly or linearly at the same interval from a subject, and the subject is photographed simultaneously by the cameras, and then the photographs are connected to one another, thereby editing images. By doing so, a still motion, like a mannequin of the subject, is displayed on a screen.
Thus, the time-slicing technique, where still images are connected to one another at various angles, has a limitation in reproduction of playing videos at various angles, in particular, a problem in that a user cannot selectively view a desired video in a particular direction.
Meanwhile, the 360 degree panoramic image technique refers to an imaging technique where photographing is performed by a camera at a fixed position through a 360 degree turn, and then a user can view an ambient space of the consecutive images through manipulation of a mouse or a touchscreen, and has been applied to road views of commercially available portal sites, and the like. This technique allows a user to directly manipulate beyond monotonous and one-sided spatial information of an existing image, thereby providing the user with fun and satisfaction. In addition, combined with web technology, the 360 degree panoramic image technique may structure and display multi-spatial information through moving lines. In addition, this technique is an imaging technology that can meet the desires of users who want to directly explore every inch of a target space by stereoscopically providing information about the surrounding space.
However, as in the time-slicing technique, the 360 degree panoramic image technique also has problems in that a playing video cannot be converted and reproduced by a user in real time at a desired angle, in particular, severe image distortion. Korean Patent Application Publication No. 10-2011-0103692, which discloses a panoramic image reproduction method, also describes a limitation on application thereof to videos. That is, when this technique is used, only a still subject spread in the 360 degree surroundings is viewed by a single camera.